Help me modify my moving average crossover script

//| A basic moving average crossover system |
#define SLEEP_OK 250
#define SLEEP_ERR 250
//---- input parameters
extern int Magic = 12347;
extern int Slippage=30; //---- bylo 30, zkousel jsem 500 a nic ....
extern double Lots=0.15;
extern int FastPeriod=15;
extern int SlowPeriod=50;
extern int Hysteresis=1; //---- bylo 4, dal jsem 1 ....
//---- static variables
static int Dig;
static double Points;
static bool Initialized = FALSE;
static bool Running = FALSE;
static bool Long = FALSE;
static double Fast;
static double Slow;
static double LastFast;
static double LastSlow;
static int OrderNumber;
static double PositionSize;
static color clBuy = DodgerBlue;
static color clSell = DarkRed;
//+------------------------------------------------------------------+
//| Utility functions |
//+------------------------------------------------------------------+
#include <stdlib.mqh>
#include <stderror.mqh>
#include <WinUser32.mqh>
//+------------------------------------------------------------------+
//| Expert helper functions |
//+------------------------------------------------------------------+
//+------------------------------------------------------------------+
//| Closes an order at market |
//+------------------------------------------------------------------+
int CloseMarket(int Ticket)
{
int Type, ErrorCode;
double Price, Quantity;
OrderSelect(Ticket, SELECT_BY_TICKET);
Type = OrderType();
Quantity = OrderLots();
while (TRUE) { // Keep trying until the order really is closed
if (Type == OP_BUY)
Price=Bid;
else if (Type == OP_SELL)
Price=Ask;
else
return (-1);
Print("CLOSE ", Ticket, ", ", Quantity, ", ", Price);
if (OrderClose(Ticket, Quantity, Price, Slippage, CLR_NONE) == TRUE) {
Sleep(SLEEP_OK);
return (0);
}
else {
ErrorCode = GetLastError();
Print("Error closing order ", Ticket, ": ", ErrorDescription(ErrorCode),
" (", ErrorCode, ")", " size: ", Quantity, ", prices: ",
Price, ", ", Bid, ", ", Ask);
Sleep(SLEEP_ERR);
RefreshRates();
}
}
return (-1);
}
//+------------------------------------------------------------------+
//| Places an order |
//+------------------------------------------------------------------+
int Order(string symbol, int Type, double Entry, double Quantity,
double TargetPrice, double StopPrice, string comment="")
{
string TypeStr;
color TypeCol;
int ErrorCode, Ticket;
double Price, FillPrice;
Price = NormalizeDouble(Entry, Dig);
switch (Type) {
case OP_BUY:
TypeStr = "BUY";
TypeCol = clBuy;
break;
case OP_SELL:
TypeStr = "SELL";
TypeCol = clSell;
break;
default:
Print("Unknown order type ", Type);
break;
}
Ticket = OrderSend(symbol, Type, Quantity, Price, Slippage,
StopPrice, TargetPrice, comment, Magic, 0, TypeCol);
if (Ticket >= 0) {
Sleep(SLEEP_OK);
if (OrderSelect(Ticket, SELECT_BY_TICKET) == TRUE) {
FillPrice = OrderOpenPrice();
if (Entry != FillPrice) {
RefreshRates();
Print("Slippage on order ", Ticket, " - Requested = ",
Entry, ", Fill = ", FillPrice, ", Current Bid = ",
Bid, ", Current Ask = ", Ask);
}
}
else {
ErrorCode = GetLastError();
Print("Error selecting new order ", Ticket, ": ",
ErrorDescription(ErrorCode), " (", ErrorCode, ")");
}
return (Ticket);
}
ErrorCode = GetLastError();
RefreshRates();
Print("Error opening ", TypeStr, " order: ", ErrorDescription(ErrorCode),
" (", ErrorCode, ")", ", Entry = ", Price, ", Target = ",
TargetPrice, ", Stop = ", StopPrice, ", Current Bid = ", Bid,
", Current Ask = ", Ask);
Sleep(SLEEP_ERR);
return (-1);
}
//+------------------------------------------------------------------+
//| Performs system initialisation |
//+------------------------------------------------------------------+
void InitSystem()
{
Running = FALSE;
PositionSize = Lots;
RefreshRates();
LastFast = iMA(Symbol(), 0, FastPeriod, 0, MODE_EMA, PRICE_MEDIAN, 0);
LastSlow = iMA(Symbol(), 0, SlowPeriod, 0, MODE_EMA, PRICE_MEDIAN, 0);
if (LastFast > LastSlow)
Long = TRUE;
Initialized = TRUE;
}
//+------------------------------------------------------------------+
//| Checks for entry to a trade - Exits previous trade also |
//+------------------------------------------------------------------+
int CheckEntry(double Size)
{
if (!Long && (Fast > (Slow + Hysteresis * Points))) {
// Fast MA crossed above slow MA so GO LONG!
if (OrderNumber > 0)
CloseMarket(OrderNumber); // Close previous short order
OrderNumber = Order(Symbol(), OP_BUY, Ask, Size, 0, 0);
if (OrderNumber > 0) {
Long = TRUE;
return(1);
}
}
else if (Long && (Fast < (Slow - Hysteresis * Points))) {
// Fast MA crossed below slow MA so GO SHORT!
if (OrderNumber > 0)
CloseMarket(OrderNumber); // Close previous long order
OrderNumber = Order(Symbol(), OP_SELL, Bid, Size, 0, 0);
if (OrderNumber > 0) {
Long = FALSE;
return(1);
}
}
return(0);
}
//+------------------------------------------------------------------+
//| Expert initialization function |
//+------------------------------------------------------------------+
int init()
{
Dig = MarketInfo(Symbol(), MODE_DIGITS);
Points = MarketInfo(Symbol(), MODE_POINT);
Print("Digits = ", Dig, ", Points = ", DoubleToStr(Points, 5));
if (!IsDemo() && !IsTesting()) {
MessageBox("Wealth Warning! This expert is for educational purposes only." +
" It should NEVER be used on a live account." +
" Past performance is in no way indicative of future results!");
Print("Initialization Failure");
return(-1);
}
InitSystem();
Print("Initialized OK");
return(0);
}
//+------------------------------------------------------------------+
//| Expert deinitialization function |
//+------------------------------------------------------------------+
int deinit()
{
Print("DeInitialized OK");
return(0);
}
//+------------------------------------------------------------------+
//| Expert start function |
//| Executed on every tick |
//+------------------------------------------------------------------+
int start()
{
if (!Initialized) {
return(-1);
}
LastFast = Fast;
LastSlow = Slow;
Fast = iMA(Symbol(), 0, FastPeriod, 0, MODE_SMA, PRICE_CLOSE, 0);
Slow = iMA(Symbol(), 0, SlowPeriod, 0, MODE_SMA, PRICE_CLOSE, 0);
if (CheckEntry(PositionSize) > 0) { // Entered a trade?
Running = TRUE; // Yes - Indicate that we're in a trade
}
return(0);
}